The present invention relates in general to apparata and methods for making woodworking joints. More specifically the present invention relates to the design of a machining guide and the arrangement of a plurality of such machining guides on a support member. Each machining guide is used to support and to guide a power tool which is used to machine two cooperating workpieces which are subsequently assembled to each other by means of one or more woodworking joints such as a dovetail joint.
One way to join together two interconnecting boards, such as when making a drawer or a piece of furniture, is to machine the cooperating portions of a dovetail joint and interlock the abutting edges of the two workpieces. A dovetail joint involves the creation of a "pin" in one workpiece and a receiving "slot" or socket in the other workpiece. If these two portions in each of the two workpieces are machined correctly, the pin fits snugly in the slot and the corner edges are able to be joined together with a smooth and flush corner joint. In the creation of furniture and drawers, a series of pins are typically created in one workpiece and a series of matching and cooperating slots are machined in the other workpiece. While dovetail joints are typically created in wooden workpieces, other materials may be used, so long as the material which is selected can be machined with the requisite degree of accuracy, by a suitable power tool such as a router.
Over the years a variety of jigs, templates, tooling arrangements and fixtures have been created for the purpose of trying to fashion dovetail pins and slots in cooperating workpieces. The following listing of U.S. patents is believed to provide a representative sampling of these earlier design efforts.
______________________________________ PATENT NO. PATENTEE ISSUE DATE ______________________________________ 5,143,132 Keller 9/01/92 5,139,062 Keller 8/18/92 4,168,730 Keller 9/25/79 4,428,408 Grisley 1/31/84 5,199,477 Keller 4/06/93 4,809,755 Pontikas 3/07/89 5,423,357 Szymanski 6/13/95 3,834,435 McCord, Jr. 9/10/74 4,407,344 Dicke 10/04/83 2,764,191 Hartmann 9/25/56 5,421,384 Nuwordu 6/06/95 ______________________________________
One of the concerns with any type of machining fixture or jig is how easy or how difficult it is to use and how reliable are the results. Another concern is how much time does it take to use the device and are there too many non-productive or wasted steps. Cost is also a concern. While woodworking may be a profession to some, it is merely a hobby to thousands of others. In order to give these hobbyists the results expected by the professionals, the fixtures and jigs need to be easy to use and consistent in their results. The device should be such that a hobbyist will not feel overwhelmed by the number of steps required to achieve the desired result. If a tooling fixture or jig is too hard to use or too time consuming, a hobbyist, and conceivably even some professionals, may lose interest and opt to change to something a little easier.
Since a dovetail-style of woodworking joint is a secure and durable joint, there is a tendency to prefer this technique to the less desirable alternatives. Therefore, if a device can be provided which is easy to use, involves only a few steps, and gives uniform, predictable, accurate, and professional results to virtually anyone, there will be a significant advance in the art based upon the eleven patents listed above. The present invention provides such a device and the versatility which is afforded by the present invention enables hobbyists as well as professionals to create accurate and precise dovetail joints with an ease and simplicity not heretofore possible.
The present invention is able to achieve these novel and unobvious results by the design of a machining guide or finger which has a shape specifically selected in cooperation with router bit configurations used to machine the two workpieces. The "slot" in one workpiece or board is created at one end of the guide finger while the "pin" in the other board is left as a by-product of the machining based upon the configuration at the other end of the guide finger. In this manner, the size and spacing between different guide fingers can be varied and yet the final joint is still properly aligned, secure and precise.